April 4, 2012 -- By following basic principles based on industry standards, it is possible to implement capacitive sensing designs with high signal-to-noise ratios that will withstand a barrage of noisy abuse. This article looks at the most relevant EMC standards and noise threats, and discusses what can be done to ensure compliance for a given capacitive sensing application.

By J.D. van Wyk, M. Visser, and D.B. Rademeyer. (van Wyk is senior application and development engineer at Azoteq; Visser is responsible for all ESD testing, and collaborates narrowly with the IC design team at Azoteq; Rademeyer manages the applications group at the Paarl Development Centre.)